RESUMEN
PURPOSE: Manifestations of infection and the degree of influenza virus vary. We hypothesized that the nose/throat microbiota modifies the duration of influenza symptoms and viral shedding. Exploring these relationships may help identify additional methods for reducing influenza severity and transmission. METHODS: Using a household transmission study in Nicaragua, we identified secondary cases of influenza virus infection, defined as contacts with detectable virus or a greater than 4-fold change in hemagglutinin inhibition antibody titer. We characterized the nose/throat microbiota of secondary cases before infection and explored whether the duration of symptoms and shedding differed by bacterial community characteristics. RESULTS: Among 124 secondary cases of influenza, higher bacterial community diversity before infection was associated with longer shedding duration (Shannon acceleration factor [AF]: 1.61, 95% confidence interval [CI]: 1.24, 2.10) and earlier time to infection (Shannon AF: 0.72, 95% CI: 0.53, 0.97; Chao1 AF: 0.992, 95% CI: 0.986, 0.998). Neisseria and multiple other oligotypes were significantly associated with symptom and shedding durations and time to infection. CONCLUSIONS: The nose/throat microbiota before influenza virus infection was associated with influenza symptoms and shedding durations. Further studies are needed to determine if the nose/throat microbiota is a viable target for reducing influenza symptoms and transmission.
Asunto(s)
Gripe Humana/transmisión , Microbiota/fisiología , Nariz/microbiología , Faringe/microbiología , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Antivirales/uso terapéutico , Niño , Preescolar , Composición Familiar , Femenino , Humanos , Lactante , Gripe Humana/tratamiento farmacológico , Masculino , Nicaragua , Oseltamivir/uso terapéutico , Reacción en Cadena en Tiempo Real de la Polimerasa , Fumar , Adulto JovenRESUMEN
Epidemiologic studies indicate that obesity increases the risk of severe complications and death from influenza virus infections, especially in elderly individuals. This work investigates the effect of obesity on the duration of viral shedding within household transmission studies in Managua, Nicaragua, over 3 seasons (2015-2017). Symptomatic obese adults were shown to shed influenza A virus 42% longer than nonobese adults (adjusted event time ratio [ETR], 1.42; 95% confidence interval [CI], 1.06-1.89); no association was observed with influenza B virus shedding duration. Even among paucisymptomatic and asymptomatic adults, obesity increased the influenza A shedding duration by 104% (adjusted ETR, 2.04; 95% CI, 1.35-3.09). These findings suggest that obesity may play an important role in influenza transmission.
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Virus de la Influenza A/fisiología , Gripe Humana/fisiopatología , Gripe Humana/virología , Obesidad/complicaciones , Obesidad/virología , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Nicaragua , Adulto JovenRESUMEN
The parapoxvirus orf virus (ORFV) is the agent of contagious ecthyma, an ubiquitous mucocutaneous disease of sheep and goats that may present variable clinical presentations. We herein studied the pathogenesis of ORFV infection in lambs and analyzed three putative virulence genes of four Brazilian ORFV isolates. Lambs inoculated in the labial commissures with each ORFV isolate (n=4, viral titer 10(5.6) TCID50/ml) developed classical orf lesions, characterized by a progressive course of erythema/macules, vesicles, pustules and proliferative scabs. Lesions lasted an average of 22.9 days (18-26) and virus shedding was detected for approximately 24.6 days (18-30). Two isolates (SV269/11 and SV820/10) produced more severe, long-lasting lesions resulting in highest clinical scores. Lambs inoculated with isolate SV581/11 developed lesions markedly milder (lower clinical scores [p<0.05]) and more limited than the other groups. Virus shedding by SV581/11 group, however, lasted similarly or even longer than the other groups. Sequence analysis of three virulence genes (VEGF, VIR and IL-10v) revealed amino acid deletions and mutations in VEGF and IL-10v genes of SV581/11 and SV252/11, the isolate(s) producing milder lesions. Additionally, the VEGF gene of isolate SV581/11 presented the lowest amino acid identity with the other isolates and with ORFV standard strain OV-IA82. Thus, these results demonstrate that ORFV isolates may display differential virulence in lambs and these differences might be associated with genetic changes in putative virulence genes.
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Ectima Contagioso/patología , Ectima Contagioso/virología , Virus del Orf/genética , Virus del Orf/patogenicidad , Secuencia de Aminoácidos , Análisis de Varianza , Animales , Secuencia de Bases , Brasil , Cartilla de ADN/genética , Interleucina-10/genética , Datos de Secuencia Molecular , Análisis de Secuencia de ADN/veterinaria , Oveja Doméstica , Especificidad de la Especie , Factor A de Crecimiento Endotelial Vascular/genética , Virulencia , Esparcimiento de Virus/fisiologíaRESUMEN
The purpose of this study is to determine the frequency of EBV and CMV DNA detection in saliva of HIV infected and non-HIV individuals and their siblings. The study group comprised 240 individuals. Group 1 comprised of 40 HIV-infected patients, group 2 40 non-HIV individuals, group 3 two siblings for each patient from group 1 (n = 80), and group 4 two siblings for each individual from group 2 (n = 80). Non-stimulated whole saliva was collected, DNA was extracted, and amplification was performed using a nested PCR protocol. EBV and CMV DNA was detected in 7/40 (17.5%) and 5/40 (12.5%) individuals from group 1, 8/40 (20%) and 3/40 (7.5%) from group 2, 11/80 (13.8%) and 2/80 (2.5%) from group 3, and 8/80 (10%) and 1/80 (1.3%) from group 4, respectively. Five (71.4%) out of seven HIV/EBV coinfected individuals of group 1 had a relative also infected with EBV (OR = 11.25, CI [1.75-72.5], p = 0.011). Regarding group 2, among the eight non-HIV and EBV-infected individuals, three (37.5%) had a relative also positive to EBV (p = 0.320). No individual HIV/CMV coinfected had a relative CMV infected (p = 1.00). Also, only one non-HIV and CMV-infected individual had a relative also positive to CMV (p = 0.075). EBV and CMV DNA was detected mainly in those who had HIV viral load counts <400/mL (71%, p = 0.2 and 100%, p = 1, respectively) and those who had CD4 T cells counts between 200 and 400/mm(3) (57%, p = 0.544 and 60%, p = 0.249, respectively). HIV-infected individuals and healthy controls showed a similar frequency of viral DNA detection. EBV DNA was significantly amplified in saliva of household members of HIV/EBV coinfected individuals.
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Citomegalovirus/fisiología , Seronegatividad para VIH , Seropositividad para VIH/virología , VIH-1/fisiología , Herpesvirus Humano 4/fisiología , Saliva/virología , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Recuento de Linfocito CD4 , Coinfección , Citomegalovirus/genética , Infecciones por Citomegalovirus/genética , Infecciones por Citomegalovirus/transmisión , ADN Viral/análisis , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/transmisión , Familia , Femenino , Seropositividad para VIH/genética , Herpesvirus Humano 4/genética , Humanos , Masculino , Persona de Mediana Edad , Hermanos , Carga Viral , Adulto JovenRESUMEN
The aim of this study was to evaluate the humoral antibody response, the genome viral excretion and the contact transmission of pathogenic chicken origin Newcastle disease virus (NDV) from experimentally infected pigeons (Columba livia) to in-contact pigeon. The antibody response to infection was assessed by the hemagglutination inhibition (HI) test and the genome viral excretion was detected by RT-PCR. Viral strain induced high antibody levels, both in inoculated and in sentinel birds. The pathogenic viral strain for chickens was unable to produce clinical signs of the disease in experimentally infected pigeons, although it induced the humoral antibody response and produced NDV genome shedding. NDV genome was detected intermittently throughout the experimental period, from 5 days post-infection (dpi) to 24 dpi. Therefore, viral genome shedding occurred for 20 days. The viral genome was detected in all birds, between 11 and 13 dpi. Furthermore, the high infectivity of the virus was confirmed, as all non-inoculated sentinel pigeons showed antibody levels as high as those of inoculated birds.
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Anticuerpos Antivirales/sangre , Columbidae , Enfermedad de Newcastle/inmunología , Virus de la Enfermedad de Newcastle/fisiología , Esparcimiento de Virus/fisiología , Animales , Formación de Anticuerpos , Genoma Viral , Enfermedad de Newcastle/transmisiónRESUMEN
PURPOSE: Herpes simplex virus type 1 (HSV-1) is a member of the human herpes virus family. Most of the population (90%) has antibodies to HSV-1, and as many as 40% of these individuals may develop secondary herpes. Shedding of HSV-1 in the oral mucosa can be induced by many factors, including stress, sunlight, menstruation, and physical trauma. The aim of the present study was to evaluate the impact of dental surgical procedures on HSV-1 shedding in the oral mucosa. PATIENTS AND METHODS: The case group comprised 48 patients undergoing third molar extraction (case group) and 48 patients undergoing conventional restorative procedures (control group). All of the patients were IgG-positive for HSV-1. Oral swabs were performed before and 1 week after the procedures to investigate HSV-1 reactivation by nested polymerase chain reaction. RESULTS: The frequency of positive oral swabs to HSV-1 in the group that underwent surgery (4.2%) was not statistically different from that in the control group (2.1%). CONCLUSIONS: The results indicate that oral surgical trauma does not have a significant impact on HSV-1 shedding in the oral mucosa.
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Restauración Dental Permanente , Herpesvirus Humano 1/fisiología , Mucosa Bucal/virología , Estomatitis Herpética/virología , Extracción Dental , Activación Viral/fisiología , Adolescente , Adulto , Anticuerpos Antivirales/sangre , ADN Viral/análisis , Electroforesis en Gel de Agar , Femenino , Estudios de Seguimiento , Herpes Labial/virología , Herpesvirus Humano 1/inmunología , Humanos , Inmunoglobulina G/sangre , Masculino , Tercer Molar/cirugía , Reacción en Cadena de la Polimerasa , Diente Impactado/cirugía , Esparcimiento de Virus/fisiologíaRESUMEN
OBJECTIVE: This study was designed to investigate the effect of allogeneic haematopoietic stem cell transplantation (HSCT) on cytomegalovirus (CMV) shedding in the saliva by nested polymerase chain reaction (nested PCR) and its impact on patient survival. PATIENTS AND METHODS: One hundred and twenty-four HSCT patients and 124 healthy volunteers were included in the study. Oral swabs were taken before, after 100 days and 1 year of HSCT at the buccal mucosa. Nested PCR was used to detect CMV in the saliva. Time of death after HSCT was displayed, by means of the Kaplan-Meier method, for the following parameters: age and gender of the patient, donor gender, primary disease, stem cell source, platelet number, chronic graft vs host disease (cGVHD) of salivary glands and oral mucosa, and oral CMV shedding. Cox proportional hazards model was used for multivariate survival analysis. RESULTS: While none of the individuals in the control group showed positive swabs for CMV, the frequency of positive CMV oral swabs in patients at day + 100 after HSCT (45.2%) was statistically higher than before (7.2%) and 1 year after HSCT (17.5%). The presence of CMV was not associated with cGVHD and did not have any impact on post-transplant survival. CONCLUSIONS: The present study shows that oral CMV shedding occurs after HSCT, especially at day +100 post-transplant. Identification of CMV in the saliva might be important for the early diagnosis of CMV infection in allo-HSTC.
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Citomegalovirus/fisiología , Trasplante de Células Madre Hematopoyéticas , Mucosa Bucal/virología , Esparcimiento de Virus/fisiología , Adolescente , Adulto , Factores de Edad , Estudios de Casos y Controles , Niño , Preescolar , Infecciones por Citomegalovirus/diagnóstico , Femenino , Estudios de Seguimiento , Enfermedad Injerto contra Huésped/virología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/virología , Recuento de Plaquetas , Saliva/virología , Enfermedades de las Glándulas Salivales/virología , Factores Sexuales , Tasa de Supervivencia , Donantes de Tejidos , Trasplante HomólogoRESUMEN
In this work, a role for the genes encoding glycoproteins I (gI) and E (gE) and the US9 protein of bovine herpesvirus type 5 (BHV-5) in neuropathogenicity and reactivation of latent infections was examined. Calves infected intranasally with a gI/gE/US9 deleted recombinant shed up to 10(2.85) TCID50/ml infectious virus in nasal secretions. Calves infected with the wild type BHV-5 parental virus shed up to 10(5) TCID50/ml virus. No signs of disease were observed in calves infected with the recombinant virus, whereas those infected with wild type virus displayed respiratory and neurological signs. The recombinant was only able to reach the basal portions of the central nervous system. In contrast, wild type virus was found widespread within the brain. Reactivation with dexamethasone 60 days post-infection resulted in reactivation of wild type virus, whereas the recombinant virus could not be reactivated. These studies demonstrate that genes gI, gE and US9 of BHV-5 are important for its neuropathogenicity and its ability to reactive from latency.